基于分支分析的机翼摇晃预测与抑制
Prediction and suppression of wing rock using bifurcation analysis

针对现代战斗机大迎角飞行时的机翼摇晃预测与抑制问题, 根据其主要动态特性建立了新的横侧向多自 由度模型, 通过开环分支分析准确预测了机翼摇晃对应的临界迎角. 在此基础上考虑模型不确定性和舵面位置限 幅的影响, 利用滤波器动态对跟踪误差进行补偿, 设计了一种约束滤波自适应反步控制算法, 通过采用补偿误差代 替跟踪误差进行自适应律设计, 确保了输入饱和条件下自适应过程的稳定, 并结合闭环分支分析实现了对机翼摇晃 运动的有效抑制. 六自由度仿真验证了多自由度模型的有效性和控制算法的鲁棒性.
To predict and suppress the wing rock phenomenon appeared at high angle of attack, a new multiple degreeof- freedom model is first established via reasonable simplifications of lateral dynamics as well as a considerate access to wing rock’s primary properties. The wing rock motion is then predicted accurately in the open-loop analysis through using the bifurcation method. On this basis, a robust constraint adaptive backstepping control algorithm is proposed in the presence of model uncertainties and external disturbances, in which a command filter is introduced to impose magnitude limit on actuators and the tracking errors are compensated by filter dynamics. Moreover, the tracking errors in adaptive laws are replaced by compensated errors which renders a stable adaptation process even though the input saturation occurs. The closed-loop bifurcation analysis show that the wing rock motion is suppressed efficiently. Finally, the effectiveness of the multiple degree-of-freedom model and robustness of the proposed control algorithm are verified by six-degree-of-freedom numerical simulation.